Tuning not holding well, help?

Recently I decided to change my string gauge from the usual 9's or 10's that I'd buy I decided to up my gauge to 11's and currently using the power slinkys 11-48. Decided to cause I use a 2mm pick and had difficulty to pick fast on thin strings.

Do I need to do something to help stable the tuning? Guy in music shop said going up to 11-48s wasn't going to affect anything.

Another thing is I generally tune to Eb standard since I be learning a lot of gnr and generally like the tuning now I've played it more.

Yeh I've strung it correctly.No its a epi les Paul custom. I've had tuning issues since I put them on and now they at point where they need changing, well I think I'm at point where I'm pushing my luck every time I play but I don't know whether to get another set of 11's I'm just hoping my current strings don't snap

If the strings are stetched and you have them on properly it's probably time for some new tuners. My old Epiphone stopped holding a tune after a while, tuners were the culprit. They are pretty cheap and easy to change.

If the strings are stetched and you have them on properly it's probably time for some new tuners. My old Epiphone stopped holding a tune after a while, tuners were the culprit. They are pretty cheap and easy to change.

Very unlikely to be the case. If there actually is something wrong with the guitar, the nut is usually the problem.

Might also be the nut. You might want to try lubricating it just in case the strings are catching.

This would be my guess. Since you've gone to thicker strings than came stock on that guitar, the nut slots may be too narrow, and the strings are binding or hanging up. Try lubricating them as other posters have mentioned. If you still have trouble you may need to file out the nut slots. It wouldn't take much.